1. Technical Field
The present invention relates generally to building materials, and more particularly to a prefinished corner bead which is adapted to serve both protective purposes and purposes of providing an attractive or decorative finish surface to both inside and outside corners of finished interior walls.
2. Background
It is common in the building trade, when finishing interior walls, to utilize a corner bead molding, particularly on outside corners, to serve the purpose of providing a durable corner bead, as well as a surface which can accept drywall compound for later finishing and painting. Corner moldings may likewise be applied to finish inside corners. Also, it is common when employing wood finishes or paneling to the surface of interior walls and the casings around interior openings, to provide some type of a corner molding to present a finished appearance and protection for the exposed corners. Once again, these types of moldings are typically applied to outside corners of interior walls where the corner is exposed to abuse, but may also be applied to inside corners for finish and protection purposes.
The prior art includes the well-known sheet metal bead which is typically employed in finishing drywall or sheetrock interior surfaces.
Additionally, the prior art describes a variety of corner moldings, including Anderson, U.S. Pat. No. 4,852,318, bullnose corner piece; Weldy, U.S. Pat. No. 5,086,598, wallboard joint reinforcing system; Rumsey, U.S. Pat. No. 4,706,426, fire-rated flush-mounted corner guard; and Attaway, U.S. Pat. No. 4,545,162, moldings.
The above-referenced patents describe a variety of items for use in a variety of circumstances. Anderson describes essentially a cap or bullnose corner piece which fits over the wall covering at an exterior corner, extending laterally along the surface of the finished wall. Anderson describes a piece which is fit up against the ends of the wall covering, as opposed to laying over the wall covering. Additionally, Anderson describes a system which is only applied to outside corners, as opposed to both interior and outside corners.
Weldy describes a wall edging system for strength reinforcing and strengthening corners and intersections of wall sections. Weldy does not provide a finished appearance and is applied directly over the wall surfacing and is intended by its description more for protection than finish.
Rumsey describes an elaborate system for protecting corners which by its nature is a fairly heavy and complicated construction in order to achieve its fire rated status. Rumsey calls out an insulating layer, a cap which overlays the insulating material, a mounting portion or mounting means which holds the cover in position by action of spring clips.
Attaway describes a rigid molding formed by extrusion which allows for a reveal which is to be exposed as a finished surface.
One objective of the present invention is to allow the builder to select from any number of finish trim veneers which are secured within the veneer recess by an adhesive. The use of a veneer provides advantages in terms of economics, choice or selection of finishes and utilization of resources. The cost of a veneer is far less than a solid finish member which would reveal the same finished surface. Additionally the availability of some fine hardwoods is diminishing, hence the use of a veneer serves to conserve these resources.
In addition, nowhere in the prior art is there described a corner molding which serves both to protect the corner from damage due to impact and which will serve an ornamental function by providing a prefinished surface, as well as providing the capacity to expand and contract with the inherent movement of structural wall systems. The present invention satisfies each of these conditions or objectives by providing a light gauge bead which is preformed for either an interior or exterior corner, the corner bead having a recessed face which is configured to accept a variety of decorative or ornamental finish trims, and the corner bead being formed in such a manner that an expansion joint is provided which may help eliminate cracking and displacement in finished wall surfaces due to the expansion and contraction of structural surfaces. Finally, the described system may be applied to both inside and outside corners.